JP7316095B2 - Vacuum dryer - Google Patents

Description

The present disclosure relates to a vacuum drying apparatus.

Patent Literature 1 discloses a reduced-pressure drying apparatus that dries a solution on a substrate housed in a chamber under reduced pressure. This vacuum drying apparatus is provided with a solvent collection net. The solvent collection net consists of a mesh plate, temporarily collects the solvent in the solution vaporized from the substrate, and is provided in the chamber so as to face the substrate. In the vacuum drying apparatus disclosed in Patent Document 1, by providing this solvent collection net, the drying time is made uniform within the plane of the substrate.

JP 2018-59597 A

The technology according to the present disclosure makes the drying time of a solution containing a plurality of solvents with different boiling points uniform over the surface of the substrate.

One aspect of the present disclosure is a reduced-pressure drying apparatus that dries a solution on a substrate under reduced pressure, wherein the solution contains a plurality of solvents having different boiling points, and the reduced-pressure drying apparatus is a container that accommodates the substrate. and a mounting table on which the substrate is mounted, and a solvent collecting part for temporarily collecting a solvent in the solution vaporized from the substrate mounted on the mounting table, in the container. and a moving mechanism for vertically moving the solvent collecting part, and the container is connected to an exhaust device for exhausting the inside of the container below the mounting table in the vicinity of the mounting table. The solvent collector is provided outside the substrate placed on the mounting table in a plan view, and is moved up and down outside the substrate by the moving mechanism. , further comprising a controller, wherein the controller moves the solvent collector downward after the solvent with a low boiling point contained in the solution is collected by the solvent collector. After the low boiling point solvent is desorbed from the solvent trapping part, the moving mechanism is controlled such that the solvent trapping part is moved upward.

According to the present invention, the drying time of a solution containing a plurality of solvents having different boiling points can be made uniform within the surface of the substrate.

It is a figure for demonstrating the subject of a prior art. BRIEF DESCRIPTION OF THE DRAWINGS It is sectional drawing which shows schematic structure of the reduced-pressure drying apparatus which concerns on 1st Embodiment. 1 is a top view showing a schematic configuration of a reduced pressure drying apparatus according to a first embodiment; FIG. FIG. 4 is a cross-sectional view showing the state inside the chamber during the reduced-pressure drying process according to the first embodiment; It is a sectional view showing a schematic structure of a reduced pressure drying device concerning a 2nd embodiment. FIG. 10 is a cross-sectional view showing the state inside the chamber during the reduced-pressure drying process according to the second embodiment; It is a sectional view showing a schematic structure of a reduced pressure drying device concerning a 3rd embodiment. FIG. 11 is a cross-sectional view showing the state inside the chamber during reduced-pressure drying processing according to the third embodiment;

2. Description of the Related Art Conventionally, an organic light emitting diode (OLED), which is a light emitting diode using organic EL (Electroluminescence) light emission, is known. Organic EL displays using such organic light-emitting diodes are thin, light, and low power consumption. In addition, they have advantages such as excellent response speed, viewing angle, and contrast ratio. In recent years, it has attracted attention as a panel display (FPD).

An organic light-emitting diode has a structure in which an organic EL layer is sandwiched between an anode and a cathode on a substrate. The organic EL layer is formed by stacking, for example, a hole injection layer, a hole transport layer, a light emitting layer, an electron transport layer and an electron injection layer in this order from the anode side. In forming each layer of these organic EL layers (especially a hole injection layer, a hole transport layer and a light emitting layer), for example, droplets of an organic material are dispersedly arranged on a substrate by an inkjet method, and pixels of each color are formed. A method is used in which the organic material film of the pixel is applied in the bank by discharging the ink to the bank corresponding to the pixel.

A large amount of solvent is contained in the organic material ejected onto the substrate by the inkjet method. Therefore, for the purpose of removing the solvent, a reduced-pressure drying process is performed to dry the solution on the substrate by reducing the pressure in the container containing the substrate.
During this reduced-pressure drying process, the drying time may become uneven within the surface of the substrate. In this case, for example, the coating film that has been dried and formed on the corners of the substrate is dissolved by the vaporized solvent in the central portion of the substrate that has not been dried. In Patent Document 1, in order to eliminate the non-uniformity of the drying time of the solution within the substrate surface as described above, a solvent collection method is proposed in which the solvent volatilizing from the organic material film on the substrate is collected by the solvent collection net. A net is provided so as to face the substrate.

By the way, the organic material discharged onto the substrate may contain both a low boiling point solvent and a high boiling point solvent. In this case, in the process of drying under reduced pressure, as shown in FIG. 1A, the low boiling point solvent S1 is vaporized, and then, as shown in FIG. 1B, the high boiling point solvent S2 is vaporized. Therefore, when the solvent collection net N is provided so as to face the substrate W as in Patent Document 1, the low boiling point solvent S1 remains in the solvent collection net N when the high boiling point solvent S2 is vaporized. , the solvent collection network N is in a state where it cannot adsorb the high boiling point solvent S2. Therefore, for the high boiling point solvent S2, it is equivalent to a state in which the solvent collection network N does not exist, so the time required for drying the solution may become uneven within the substrate surface.

Therefore, the technology according to the present disclosure makes the drying time of a solution containing a plurality of solvents with different boiling points uniform within the surface of the substrate.

Hereinafter, a reduced pressure drying apparatus and a reduced pressure drying method according to the present embodiment will be described with reference to the drawings. In the present specification and drawings, elements having substantially the same functional configuration are denoted by the same reference numerals, thereby omitting redundant description.

(First embodiment)
2 and 3 are diagrams showing a schematic configuration of the reduced-pressure drying apparatus according to the first embodiment, FIG. 2 being a cross-sectional view and FIG. 3 being a top view. In addition, in FIG. 3, the illustration of the top plate etc. mentioned later is abbreviate|omitted.

The reduced-pressure drying apparatus 1 shown in FIG. 2 dries a solution applied on a substrate W by, for example, an ink jet method under reduced pressure. The substrate W to be processed by the reduced pressure drying apparatus 1 is, for example, a large glass substrate for an organic EL display, and its planar size is, for example, 2.2 m×2.5 mm.

The solution applied to the substrate W to be processed is composed of a solute and a solvent, and the component to be dried under reduced pressure is mainly the solvent.
In addition, a mixture of a low boiling point solvent and a high boiling point solvent is used as a solvent in the solution.
In this embodiment, the low boiling point is, for example, 200 to 230° C., and the high boiling point is 250° C. or higher. In this case, examples of the low boiling point solvent include 4-tert-butylanisole. Moreover, as a high boiling point solvent, dodecylbenzene can be mentioned, for example.
In addition, the low boiling point and the high boiling point are relative, and there are various determination methods from experiments and the like. , can be appropriately selected and used.
1,3-dimethyl-2-imidazolidinone (boiling point 220°C, melting point 8°C), 4-tert-Butylanisole (boiling point 222°C, melting point 18) °C), Trans-Anethole (boiling point 235°C, melting point 20°C), 1,2-Dimethoxybenzene (boiling point 206.7°C, melting point 22.5°C), 2-Methoxybiphenyl , boiling point 274°C, melting point 28°C), Phenyl Ether (boiling point 258.3°C, melting point 28°C), 2-Ethoxynaphthalene (boiling point 282°C, melting point 35°C), Benzyl Phenyl Ether , boiling point 288°C, melting point 39°C), 2,6-Dimethoxytoluene (boiling point 222°C, melting point 39°C), 2-Propoxynaphthalene (boiling point 305°C, melting point 40°C), 1,2,3-Trimethoxybenzene (boiling point 235°C, melting point 45°C), cyclohexylbenzene (boiling point 237.5°C, melting point 5°C), dodecylbenzene (boiling point 288°C, Melting point -7℃), 1,2,3,4-tetramethylbenzene (1,2,3,4-tetramethylbenzene, boiling point 203℃, melting point 76℃)

The reduced-pressure drying apparatus 1 includes a chamber 10 which is configured to be capable of being reduced in pressure and which is a container for accommodating substrates W therein.

The chamber 10 is made of a metal material such as stainless steel. Further, the chamber 10 has a rectangular tube-shaped main body portion 11 with openings formed in the upper and lower sides.
A loading/unloading port (not shown) for loading/unloading the substrate W into/from the chamber 10 is provided on the side wall of the main body 11 . Further, a top plate 12 is attached so as to block an opening on the upper side of the main body portion 11 , and a bottom plate 13 is mounted so as to close the opening on the lower side of the main body portion 11 .

A mounting table 20 is provided substantially in the center of the chamber 10 . The substrate W is horizontally placed on the upper surface of the mounting table 20, which is the substrate mounting surface 20a. Moreover, the mounting table 20 is formed in a rectangular shape larger than the substrate W in plan view. An upper end portion of a vertically extending support member 21 is connected to the central portion of the lower surface of the mounting table 20 . A lower end of the support member 21 is connected to the bottom plate 13 of the chamber 10 . A lifting pin (not shown) is provided for the mounting table 20 so as to pass through the mounting table 20 . The elevating pins are for transferring the substrate W from the outside of the chamber 10 to a substrate transfer device (not shown) inserted into the chamber 10 . The elevating pin is configured to be freely movable up and down by an elevating mechanism (not shown).

In the chamber 10, a plurality of exhaust ports 13a are formed around the mounting table 20 and below the substrate mounting surface 20a of the mounting table 20. As shown in FIG. Specifically, for example, as shown in FIG. 3, in a region of the bottom plate 13 of the chamber 10 that does not overlap the mounting table 20 in plan view (that is, outside the mounting table 20), each of the mounting tables 20 in plan view is provided. Four exhaust ports 13a are formed along the long side.

One end of an exhaust pipe 30 is connected to each of the exhaust ports 13a as shown in FIG. The other end of each exhaust pipe 30 is connected to an exhaust device P that exhausts the interior of the chamber 10 to reduce the pressure. The evacuation device P is composed of a vacuum pump, for example, a turbo-molecular pump and a dry pump, which are connected in series in this order from the upstream side. An automatic pressure control valve (APC (Adaptive Pressure Control) valve) 31 is provided upstream of the exhaust system in the exhaust pipe 30 . In the reduced-pressure drying apparatus 1, the degree of vacuum in the chamber 10 during evacuation can be controlled by adjusting the opening degree of the APC valve 31 while the vacuum pump of the evacuation device P is in operation.
A pressure gauge (not shown) for measuring the pressure inside the chamber 10 is provided in the reduced-pressure drying apparatus 1 in order to control the degree of vacuum by the APC valve 31 . A measurement result of the pressure gauge is input to the APC valve 31 as an electric signal.
A protective cover (not shown) is attached to the exhaust port 13 a to prevent foreign matter from entering the exhaust device P and the APC valve 31 .

Further, the chamber 10 is provided with a solvent collector 40 for temporarily collecting the solvent in the solution vaporized from the substrate W mounted on the mounting table 20 . Specifically, the solvent collection unit 40 collects the solvent vaporized from the solution applied onto the substrate W by the inkjet method. By providing the solvent collector 40 inside the chamber 10 , the concentration of the solvent in the atmosphere inside the chamber 10 can be adjusted.

The solvent collecting part 40 is arranged so as to be positioned outside the substrate W placed on the placing table 20 in plan view. In the present embodiment, the solvent collector 40 is arranged at a position overlapping with the exhaust port 13a formed around the mounting table 20 in plan view. Therefore, as compared with the case where it is disposed at a position facing the substrate W, an airflow passing through the mesh of the solvent collecting section 40 and directed toward the exhaust port 13a is more likely to be formed, and adsorption and desorption of the solvent are more likely to proceed.

The shape of the solvent collecting part 40 is, for example, an angular annular shape that surrounds the outside of the mounting table 20 in plan view. Further, the solvent collecting part 40 has, for example, a plurality of rectangular members (hereinafter referred to as “divided members”) 41 in plan view, and four divided members 41 in the illustrated example. By arranging the dividing members 41 along the side wall of the main body 11 of the chamber 10, the solvent collecting section 40 as a whole forms an angular annular shape as described above.
Each divided member 41 of the solvent collecting portion 40 includes a solvent collecting net (not shown) which is a plate-like member, that is, a mesh plate in which openings penetrating in the thickness direction are regularly formed in a lattice shape when viewed from above. have. The solvent trapping net is made of a material having good thermal conductivity, such as stainless steel, aluminum, copper, or gold. More specifically, it is composed of expanded metal manufactured by cold rolling a steel plate. Also, the solvent collection net is formed so as to have a small heat capacity.
The divided members 41 of the solvent collecting section 40 are supported from below by supporting members 52, which will be described later.

Furthermore, the chamber 10 has a moving mechanism 50 for vertically moving the solvent collector 40 described above.
The moving mechanism 50 has a rail 51 , a support member 52 and a drive section 53 .
The rail 51 is a vertically extending member fixed to the side wall of the main body 11 of the chamber 10 .
The support member 52 is a member that extends in the horizontal direction (horizontal direction in the drawing) and supports the solvent trapping section 40 , specifically, the dividing member 41 of the solvent trapping section 40 . The support member 52 is movable along the rails 51 by the driving portion 53 . With this configuration, the solvent collector 40 can move up and down.

The reduced-pressure drying apparatus 1 also has a control unit U. As shown in FIG. The control unit U is, for example, a computer equipped with a CPU, memory, etc., and has a program storage unit (not shown). The program storage unit stores a program for controlling the reduced pressure drying process in the reduced pressure drying apparatus 1 . The program may be recorded in a computer-readable storage medium and installed in the control unit from the storage medium. Part or all of the program may be realized by dedicated hardware (circuit board).

Subsequently, the reduced pressure drying process using the reduced pressure drying apparatus 1 will be described with reference to FIG. FIG. 4 is a sectional view showing the state inside the chamber 10 during the drying process under reduced pressure.

In the reduced-pressure drying process using the reduced-pressure drying apparatus 1 , first, the substrate W coated with the solution by the inkjet method is mounted on the mounting table 20 .
Next, the dry pump of the evacuation device P is operated and the inside of the chamber 10 is evacuated. Evacuation by the dry pump is performed until the pressure in the chamber 10 reaches 10 Pa, for example.
Subsequently, the turbo-molecular pump of the evacuation device P is operated, and the inside of the chamber 10 is further evacuated.

During the evacuation, the gas in the chamber 10 is cooled by adiabatic expansion, and the cooled gas cools the solvent collector 40 with a small heat capacity located at the adsorption position, which will be described later. As a result, the temperature of the solvent collector 40 becomes lower than the dew point (for example, 8 to 15° C.) of the low boiling point solvent and the high boiling point solvent at the pressure inside the chamber 10 at each time point.
The temperature of the solvent collector 40 is maintained below the dew point of the pressure inside the chamber 10 at each time point until the evaporation of the solvent on the substrate W is completed.

Further, when the pressure in the chamber 10 reaches P1 due to the above-described evacuation, the vapor pressure of the low-boiling-point solvent (meaning the vapor pressure at the temperature of the substrate W at that time; the same shall apply hereinafter), FIG. , the low boiling point solvent S1 evaporates. The vaporized low-boiling-point solvent S1 is adsorbed by the solvent collector 40 at the adsorption position, which is cooled as described above. The adsorption position is a predetermined position in the vertical direction where the solvent can be adsorbed so that the solvent is uniformly dried within the substrate surface.

At the timing when drying of the low boiling point solvent S1 on the substrate W is completed, the solvent collector 40 is lowered to a drying position below the mounting table 20 and near the exhaust port 13a, as shown in FIG. 4(B). be done. This is to remove the low boiling point solvent S1 adsorbed to the solvent collection portion 40 from the solvent collection portion 40 . By descending as described above, the low boiling point solvent S1 adsorbed on the solvent collecting section 40 is quickly removed. The low boiling point solvent S1 desorbed from the solvent collection part 40 is discharged through the exhaust port 13a. Note that "the timing at which the drying of the low boiling point solvent S1 on the substrate W is completed" is specifically, for example, the timing at which a predetermined time has elapsed after the turbo-molecular pump of the exhaust device P starts operating. .

Then, at the timing when the removal of the low boiling point solvent S1 collected by the solvent collection unit 40 is completed, the solvent collection unit 40 is returned to the adsorption position above the drying position as shown in FIG. 4(C). be Note that the “timing at which the removal of the low-boiling-point solvent S1 collected by the solvent collection unit 40 is completed” is, for example, the timing at which a predetermined time has elapsed after the turbo-molecular pump of the exhaust device P starts operating. be.

After that, when the pressure in the chamber 10 decreases and reaches the vapor pressure P2 of the high boiling point solvent S2, the high boiling point solvent S2 evaporates. At this point, the low boiling point solvent S1 has been removed from the solvent collecting section 40, so the vaporized high boiling point solvent S2 is adsorbed by the solvent collecting section 40. FIG. In other words, the solvent collector 40 functions also for the high boiling point solvent S2. Therefore, the time required for drying the high boiling point solvent S2 becomes uniform within the substrate surface.

Even after the removal of the high boiling point solvent S2 on the substrate W is completed, the evacuation by the turbomolecular pump of the evacuation device P is continued. This is for removing the high boiling point solvent S2 collected by the solvent collection unit 40 from the solvent collection unit 40 . The high boiling point solvent S2 desorbed from the solvent collection part 40 is discharged through the exhaust port 13a.
For example, the step of removing the high-boiling solvent from the solvent collector 40 is completed by continuing the evacuation by the turbo-molecular pump until a predetermined time has elapsed since the turbo-molecular pump was operated.
During this step, the solvent collector 40 may be lowered to a position near the exhaust port 13a.

After the process of removing the high boiling point solvent from the solvent collecting section 40 is completed, the exhaust device P is stopped. Thereafter, the substrate W is unloaded from the chamber 10 after the pressure inside the chamber 10 is returned to the atmospheric pressure. This completes the reduced pressure drying process using the reduced pressure drying apparatus 1 .

As described above, in the present embodiment, the exhaust port 13a is provided below the mounting table 20 around the mounting table 20, and the solvent collecting part 40 is mounted on the mounting table in plan view. provided in a region outside the substrate W. Furthermore, in the present embodiment, a moving mechanism 50 is provided for moving the solvent collecting portion 40 in the vertical direction. Therefore, after the removal of the low-boiling-point solvent S1 on the substrate W is completed, the low-boiling-point solvent S1 adsorbed by the solvent-collecting unit 40 is removed by, for example, moving down the solvent collecting unit 40 toward the exhaust port 13a side. It can be quickly removed from the collecting section 40 . Therefore, the low boiling point solvent S1 vaporized from the substrate W and adsorbed to the solvent collecting section 40 can be desorbed and discharged from the solvent collecting section 40 at the time when the high boiling point solvent S2 is vaporized. . Therefore, when vaporizing the high boiling point solvent S2 on the substrate W, the high boiling point solvent S2 can be adsorbed by the solvent collecting section 40, that is, the solvent collecting section 40 can function. As a result, the time required for drying the solution containing both the low boiling point solvent S1 and the high boiling point solvent S2 can be made uniform within the substrate surface. In addition, it is possible to prevent variations in the shape of the film within the pixel within the substrate W, variations in the film thickness distribution within the substrate W, and variations in the film thickness distribution within one pixel.

Furthermore, in the present embodiment, the low boiling point solvent is quickly removed from the solvent collecting section 40, so that the pressure inside the chamber 10 can reach the vapor pressure of the high boiling point solvent S2 quickly. Therefore, it is possible to shorten the time until drying of the high boiling point solvent from the substrate W is completed.

Furthermore, during the step of removing the high-boiling-point solvent collected by the solvent collection unit 40, by lowering the solvent collection unit 40 to a drying position near the exhaust port 13a, A high boiling point solvent can be removed quickly. Therefore, it is possible to shorten the time required for the entire vacuum drying process including the drying of the solvent collecting section 40 .

In the present embodiment, the solvent collecting part 40 is provided with the exhaust port 13a not only in the region facing the long side of the mounting table 20, which is the region in which the exhaust port 13a is provided in plan view. It is also provided in an area facing the short side of the mounting table 20, which is an area where there is no area. However, the portion of the solvent collector 40 provided in the region facing the short side of the mounting table 20 may be omitted.
Further, in the present embodiment, the solvent trapping portion 40 is provided so as to form an angular ring in plan view. The dashed-dotted line portion K) may be omitted. This is to prevent the substrate corners, which tend to dry quickly, from drying quickly.

The openings of the solvent collection nets of the divided members 41 of the solvent collection unit 40 are formed, for example, so that the opening ratio is uniform within the surface of the solvent collection net. Alternatively, the heat capacity may be made uneven in the plane of the solvent collection net so that the heat capacity varies depending on the location. For example, portions of the solvent trapping network near the corners of the substrate may have a smaller opening ratio to increase the heat capacity, and other portions may have a larger opening ratio to decrease the heat capacity. The smaller the heat capacity, the easier it is to cool and the easier it is to adsorb the solvent. Therefore, by configuring as described above, it is possible to prevent the corners of the substrate, which tend to dry quickly, from drying quickly.

In the example shown in FIG. 2 and the like, each divided member 41 of the solvent collector 40 is arranged so as to extend in the horizontal direction. may be arranged to extend in the direction of

Further, in the above example, the exhaust port 13 a is provided in the bottom plate 13 . It may be provided on the side wall.

In the illustrated example, the above-mentioned adsorption position as the position of the solvent collector 40 is above the mounting table 20, but is between the mounting table 20 and the exhaust port 13a in the vertical direction. may

(Second embodiment)
FIG. 5 is a cross-sectional view showing a schematic configuration of a reduced-pressure drying apparatus according to the second embodiment.
In the second embodiment, as shown in FIG. 5, the vacuum drying apparatus 1a has a solvent collector 60 similar to the solvent collector 40, and these solvent collectors 40 and 60 are stacked vertically. ing. In this embodiment, the solvent collector 40 is arranged in the lower stage, and the solvent collector 60 is arranged in the upper stage. Further, the vacuum drying apparatus 1a further has a moving mechanism 70 for moving the solvent collecting part 60 in the vertical direction.

The moving mechanism 70 has a support member 71 and a drive section 72 . The rail 51 is shared by the moving mechanism 70 and the moving mechanism 50 .
The support member 71 is a member extending in the horizontal direction (horizontal direction in the figure) and supports the solvent collector 60 . The support member 71 is movable along the rail 51 by a driving portion 62 provided above the driving portion 53 . With this configuration, the solvent collector 60 can move up and down above the solvent collector 40 .

Next, with regard to the reduced-pressure drying process using the reduced-pressure drying apparatus 1a, the differences from the reduced-pressure drying process using the reduced-pressure drying apparatus 1 of the first embodiment will be described with reference to FIG. FIG. 6 is a sectional view showing the state inside the chamber 10 of the reduced pressure drying apparatus 1a during the reduced pressure drying process.

In the reduced pressure drying process using the reduced pressure drying device 1a, the inside of the chamber 10 is evacuated by the dry pump and the turbomolecular pump of the evacuation device P, and when the pressure inside the chamber 10 reaches the vapor pressure P1 of the low boiling point solvent, FIG. As shown in (A), the low boiling point solvent S1 is vaporized. Since the solvent trapping portion 40 at the adsorption position is cooled due to the adiabatic expansion due to the evacuation, the vaporized low boiling point solvent S1 is adsorbed by the solvent trapping portion 40 .
At this time, the solvent collecting unit 60 is positioned at the standby position above the adsorption position, is far from the substrate W, and is not cooled as compared to the solvent collecting unit 40. Therefore, the solvent collecting unit 60 does not adsorb the low boiling point solvent S1.

At the timing when drying of the low boiling point solvent S1 on the substrate W is completed, the solvent collector 40 is lowered to the drying position near the exhaust port 13a as shown in FIG. The collecting portion 60 is lowered to the suction position. By lowering the solvent collecting portion 40 to the drying position, the low boiling point solvent S1 adsorbed to the solvent collecting portion 40 is removed. Further, by lowering the solvent trapping part 60 to the adsorption position, the solvent trapping part 60 is cooled by the gas inside the chamber 10 cooled by adiabatic expansion during evacuation.

Then, when the pressure in the chamber 10 decreases and reaches the vapor pressure P2 of the high boiling point solvent S2, the high boiling point solvent S2 vaporizes. The vaporized high boiling point solvent S2 is adsorbed by the cooled solvent collector 60 .

At the timing when the drying of the high boiling point solvent S2 on the substrate W is completed, the solvent collector 60 is moved to the lower position as shown in FIG. be. As a result, the high boiling point solvent S2 adsorbed on the solvent collection part 60 is quickly removed. Note that "the timing at which the drying of the high-boiling-point solvent S2 on the substrate W is completed" is, for example, the timing at which a predetermined time has elapsed after the turbo-molecular pump of the exhaust device P starts operating. .

As described above, in the present embodiment, the solvent collectors 40 and 60 are stacked, and the moving mechanisms 50 and 70 that move the solvent collectors 40 and 60 in the vertical direction are provided. Therefore, the solvent collector 60 can absorb the high boiling solvent S2 while removing the low boiling solvent S1 absorbed by the solvent collector 40 from the solvent collector 40 . In the first embodiment, the low boiling point solvent S1 is removed from the solvent collection unit 40 when the pressure inside the chamber 10 reaches the vapor pressure P2 of the high boiling point solvent S2. In some cases, the removal of the low boiling point solvent S1 is not completed when the reaction is carried out. Even in this case, in the present embodiment, the high boiling point solvent S2 can be adsorbed by the solvent collector 60 from the stage when the pressure in the chamber 10 reaches the vapor pressure P2 of the high boiling point solvent S2. The time required for drying the solution containing both S1 and high boiling point solvent S2 can be more reliably made uniform within the substrate surface.

Furthermore, during the drying step of the high-boiling-point solvent collected by the solvent collection unit 60, the solvent collection unit 60 is lowered to a position near the exhaust port 13a, and the high boiling point solvent adsorbed by the solvent collection unit 60 is The boiling point solvent is removed quickly. Therefore, it is possible to shorten the time required for the entire vacuum drying process including the drying of the solvent collecting section 60 .

(Third Embodiment)
FIG. 7 is a cross-sectional view showing a schematic configuration of a vacuum drying apparatus according to the third embodiment.
In the third embodiment, as shown in FIG. 7, the reduced-pressure drying device 1b is provided in addition to the solvent collector 40 to face the substrate W mounted on the mounting table 20. It has a collecting portion 80 . Further, the reduced-pressure drying apparatus 1b further has another moving mechanism 90 for vertically moving the solvent collector 80. As shown in FIG.

The moving mechanism 90 has a support member 91 .
The support member 91 is a member configured to be vertically extendable, and supports the solvent collecting section 80 from above. One end of the support member 91 is connected to the solvent collector 80 and the other end is connected to the top plate 12 . With this configuration, the solvent collector 80 can move up and down.

Subsequently, with regard to the reduced-pressure drying process using the reduced-pressure drying apparatus 1b, the differences from the reduced-pressure drying process using the reduced-pressure drying apparatus 1 of the first embodiment and the reduced-pressure drying apparatus 1a of the second embodiment will be described with reference to FIG. explain. FIG. 8 is a sectional view showing the state inside the chamber 10 of the reduced pressure drying apparatus 1b during the reduced pressure drying process.

In the reduced-pressure drying process using the reduced-pressure drying device 1b, the inside of the chamber 10 is evacuated by the dry pump and the turbo-molecular pump of the evacuation device P, and when the pressure inside the chamber 10 reaches the vapor pressure P1 of the low-boiling-point solvent, FIG. As shown in (A), the low boiling point solvent S1 is vaporized. Since the solvent trapping portion 40 at the adsorption position is cooled due to the adiabatic expansion due to the evacuation, the vaporized low boiling point solvent S1 is adsorbed by the solvent trapping portion 40 .
At this time, the solvent collector 80 is located at the standby position, far from the substrate W, and is not cooled as compared to the solvent collector 40. Therefore, the solvent collector 80 contains the low-boiling-point solvent S1. is not adsorbed.

At the timing when the drying of the low boiling point solvent S1 on the substrate W is completed, the solvent collector 40 is lowered to the drying position near the exhaust port 13a as shown in FIG. The collecting portion 80 is lowered to the suction position. By lowering the solvent collecting portion 40 to the drying position, the low boiling point solvent S1 adsorbed to the solvent collecting portion 40 is removed. Further, by lowering the solvent trapping part 80 to the adsorption position, the solvent trapping part 80 is cooled by the gas inside the chamber 10 that has been cooled by adiabatic expansion during evacuation.

Then, when the pressure in the chamber 10 decreases and reaches the vapor pressure P2 of the high boiling point solvent S2, the high boiling point solvent S2 vaporizes. The vaporized high boiling point solvent S2 is adsorbed by the cooled solvent collector 80 .

Even after the removal of the high boiling point solvent S2 on the substrate W is completed, the evacuation by the turbomolecular pump of the evacuation device P is continued. This is to remove the high boiling point solvent S2 collected by the solvent collection unit 80 from the solvent collection unit 80, as shown in FIG. 8(C).

As described above, in this embodiment, the solvent collector 80 facing the substrate W mounted on the mounting table 20 and another moving mechanism 90 for vertically moving the solvent collector 80 are provided. ing. Therefore, the solvent collector 80 can absorb the high boiling solvent S2 while removing the low boiling solvent S1 adsorbed to the solvent collector 40 from the solvent collector 40 . Therefore, as in the second embodiment, the time required for drying the solution containing both the low boiling point solvent S1 and the high boiling point solvent S2 can be more reliably made uniform within the substrate surface.

In this embodiment, the solvent collector 40 adsorbs the low boiling point solvent S1 and the solvent collector 80 adsorbs the high boiling point solvent S2. The solvent collection unit 80 may absorb the low boiling point solvent S1.

In the above description, the solvent contained in the solution applied to the substrate to be processed is a mixed solvent of two types of solvents, a low boiling point solvent and a high boiling point solvent. A mixed solvent of three or more solvents may be used.
When using a mixed solvent of three or more solvents described above, for example, in the second embodiment, the solvent collection net is laminated in three or more stages, and in the fourth embodiment, the substrate W on the mounting table 20 in plan view The solvent collector positioned outside is laminated in two or more stages.

The non-uniformity of the drying time of the solvent within the substrate plane becomes more conspicuous as the substrate W increases in size. Therefore, the reduced-pressure drying apparatus according to each of the embodiments described above is particularly useful when a large-sized substrate W is to be subjected to drying processing.

It should be considered that the embodiments disclosed this time are illustrative in all respects and not restrictive. The embodiments described above may be omitted, substituted, or modified in various ways without departing from the scope and spirit of the appended claims.

Note that the following configuration also belongs to the technical scope of the present disclosure.
(1) A vacuum drying apparatus for drying a solution on a substrate under reduced pressure,
The solution contains a plurality of solvents having different boiling points,
The reduced-pressure drying device has a container that accommodates the substrate,
in said container,
a mounting table on which the substrate is mounted;
a solvent collecting part for temporarily collecting a solvent in the solution vaporized from the substrate placed on the mounting table;
a movement mechanism for vertically moving the solvent collector;
has
The container is
An exhaust port connected to an exhaust device for exhausting the inside of the container is provided below the mounting table in the vicinity of the mounting table,
The reduced-pressure drying apparatus, wherein the solvent collecting section is provided outside the substrate placed on the mounting table in a plan view, and is vertically moved outside the substrate by the moving mechanism.
According to the above (1), the exhaust port is provided below the mounting table in the periphery of the mounting table, and the solvent collector is a region outside the substrate mounted on the mounting table in plan view. is provided in Further, a moving mechanism is provided for vertically moving the solvent collector. Therefore, after the removal of the low-boiling-point solvent on the substrate is completed, the low-boiling-point solvent adsorbed to the solvent-collecting portion is quickly removed from the solvent-collecting portion by, for example, moving the solvent-collecting portion downward toward the exhaust port side. can do. Therefore, the solvent collector can function when removing the high boiling point solvent next to the low boiling point solvent from the substrate. Therefore, the time required for drying the solution containing both the low boiling point solvent and the high boiling point solvent can be made uniform within the substrate surface.
Moreover, according to the above (1), for example, it is possible to shorten the time until the drying of the high boiling point solvent from the substrate is completed.

(2) having a control unit;
The control unit
After the solvent with a low boiling point contained in the solution is collected by the solvent collector, the solvent collector is moved downward,
After the low boiling point solvent is desorbed from the downwardly moved solvent collector, the movement mechanism is controlled such that the solvent collector is moved upward. The vacuum drying apparatus according to (1) above.

(3) a plurality of the solvent traps are stacked in the vertical direction;
The reduced-pressure drying apparatus according to (1), wherein the moving mechanism vertically moves the plurality of stacked solvent collecting portions.
According to the above (3), the time required for drying the solution containing both the low boiling point solvent and the high boiling point solvent can be more reliably made uniform within the substrate surface.
In addition, the time required for the entire vacuum drying process including drying of the solvent trap can be shortened.

(4) having a control unit;
After the low-boiling-point solvent contained in the solution is collected by the lower solvent collection unit among the multiple-layered solvent collection units, the control unit controls the solvent-collection unit. The reduced-pressure drying apparatus according to (3) above, configured to control the moving mechanism such that the collecting portion is moved downward.

(5) The reduced-pressure drying apparatus according to (1) above, further comprising another solvent collector provided so as to face the substrate mounted on the mounting table.
According to the above (5), the time required for drying the solution containing both the low boiling point solvent and the high boiling point solvent can be more reliably made uniform within the substrate surface.

(6) another moving mechanism for vertically moving the another solvent collecting part;
having a control unit,
The control unit controls the another moving mechanism so that the another solvent collecting unit is moved downward after the low boiling point solvent contained in the solution is collected by the solvent collecting unit. The vacuum drying apparatus according to (5) above, which is configured as follows.

(7) A reduced pressure drying method for drying the solution on the substrate under reduced pressure using a reduced pressure drying apparatus,
The solution contains a plurality of solvents having different boiling points,
The vacuum drying device is
Having a container that accommodates the substrate,
in said container,
a mounting table on which the substrate is mounted;
a solvent collecting part that temporarily collects a solvent in the solution vaporized from the substrate placed on the mounting table;
The container has
An exhaust port connected to an exhaust device for exhausting the inside of the container is provided below the mounting table in the vicinity of the mounting table,
The solvent collector is provided outside the substrate mounted on the mounting table in a plan view,
The reduced pressure drying method is
a step of evacuating the inside of the container and collecting a low boiling point solvent contained in the solution with the solvent collection unit;
A step of evacuating the container, following the step of collecting the low boiling point solvent, to desorb the low boiling point solvent collected in the solvent collecting portion;
a step of removing the low boiling point solvent, followed by the step of evacuating the inside of the container and collecting the high boiling point solvent contained in the solution with the solvent collection unit.

1, 1a, 1b vacuum drying device 10 chamber 13a exhaust port 20 mounting table 40, 60, 80 solvent collector P exhaust device S1 low boiling point solvent S2 high boiling point solvent W substrate

Claims (6)

A reduced pressure drying apparatus for drying a solution on a substrate under reduced pressure,
The solution contains a plurality of solvents having different boiling points,
The reduced-pressure drying device has a container that accommodates the substrate,
in said container,
a mounting table on which the substrate is mounted;
a solvent collecting part for temporarily collecting a solvent in the solution vaporized from the substrate placed on the mounting table;
a movement mechanism for vertically moving the solvent collector;
has
The container is
An exhaust port connected to an exhaust device for exhausting the inside of the container is provided below the mounting table in the vicinity of the mounting table,
The solvent collector is provided outside the substrate placed on the mounting table in a plan view, and is vertically moved outside the substrate by the movement mechanism ,
further comprising a control unit;
The control unit
After the solvent with a low boiling point contained in the solution is collected by the solvent collector, the solvent collector is moved downward,
After the low boiling point solvent is desorbed from the downwardly moved solvent collector, the movement mechanism is controlled such that the solvent collector is moved upward. Vacuum dryer. A reduced pressure drying apparatus for drying a solution on a substrate under reduced pressure,
The solution contains a plurality of solvents having different boiling points,
The reduced-pressure drying device has a container that accommodates the substrate,
in said container,
a mounting table on which the substrate is mounted;
a solvent collecting part for temporarily collecting a solvent in the solution vaporized from the substrate placed on the mounting table;
a movement mechanism for vertically moving the solvent collector;
has
The container is
An exhaust port connected to an exhaust device for exhausting the inside of the container is provided below the mounting table in the vicinity of the mounting table,
The solvent collector is provided outside the substrate placed on the mounting table in a plan view, is vertically moved by the moving mechanism outside the substrate, and has a plurality of solvent collectors in the vertical direction. laminated,
The moving mechanism moves the plurality of stacked solvent collectors in a vertical direction,
further comprising a control unit;
After the low-boiling-point solvent contained in the solution is collected by the lower solvent collection unit among the multiple-layered solvent collection units, the control unit controls the solvent-collection unit. A vacuum drying apparatus configured to control the moving mechanism such that the collecting portion is moved downward. A reduced pressure drying apparatus for drying a solution on a substrate under reduced pressure,
The solution contains a plurality of solvents having different boiling points,
The reduced-pressure drying device has a container that accommodates the substrate,
in said container,
a mounting table on which the substrate is mounted;
a solvent collecting part for temporarily collecting a solvent in the solution vaporized from the substrate placed on the mounting table;
a movement mechanism for vertically moving the solvent collector;
has
The container is
An exhaust port connected to an exhaust device for exhausting the inside of the container is provided below the mounting table in the vicinity of the mounting table,
The solvent collector is provided outside the substrate placed on the mounting table in a plan view, and is vertically moved outside the substrate by the movement mechanism,
another solvent collector provided to face the substrate mounted on the mounting table;
another moving mechanism for vertically moving the another solvent collecting part;
further comprising a control unit ;
The control unit controls the another moving mechanism so that the another solvent collecting unit is moved downward after the low boiling point solvent contained in the solution is collected by the solvent collecting unit. A vacuum drying apparatus configured as follows. A reduced pressure drying method for drying a solution on a substrate under reduced pressure using a reduced pressure drying apparatus,
The solution contains a plurality of solvents having different boiling points,
The vacuum drying device is
Having a container that accommodates the substrate,
in said container,
a mounting table on which the substrate is mounted;
a solvent collecting part that temporarily collects a solvent in the solution vaporized from the substrate placed on the mounting table;
The container has
An exhaust port connected to an exhaust device for exhausting the inside of the container is provided below the mounting table in the vicinity of the mounting table,
wherein the solvent collector is provided outside the substrate placed on the mounting table in a plan view, and is vertically moved outside the substrate;
The reduced pressure drying method is
a step of, after collecting the low-boiling-point solvent contained in the solution with the solvent collector, moving the solvent collector downward;
desorbing the low-boiling-point solvent from the downwardly moved solvent collecting portion, and then moving upwardly the solvent collecting portion. A reduced pressure drying method for drying a solution on a substrate under reduced pressure using a reduced pressure drying apparatus,
The solution contains a plurality of solvents having different boiling points,
The vacuum drying device is
Having a container that accommodates the substrate,
in said container,
a mounting table on which the substrate is mounted;
a solvent collecting part that temporarily collects a solvent in the solution vaporized from the substrate placed on the mounting table;
The container has
An exhaust port connected to an exhaust device for exhausting the inside of the container is provided below the mounting table in the vicinity of the mounting table,
The solvent collecting part is provided outside the substrate placed on the mounting table in plan view, is moved in the vertical direction outside the substrate, and is stacked in a plurality in the vertical direction,
In the reduced-pressure drying method, a low-boiling-point solvent contained in the solution is collected by the lower solvent collection unit among the multiple-layered solvent collection units, and A reduced-pressure drying method comprising the step of moving the collecting portion downward . A reduced pressure drying method for drying a solution on a substrate under reduced pressure using a reduced pressure drying apparatus,
The solution contains a plurality of solvents having different boiling points,
The vacuum drying device is
Having a container that accommodates the substrate,
in said container,
a mounting table on which the substrate is mounted;
a solvent collecting part that temporarily collects a solvent in the solution vaporized from the substrate placed on the mounting table;
The container has
An exhaust port connected to an exhaust device for exhausting the inside of the container is provided below the mounting table in the vicinity of the mounting table,
wherein the solvent collector is provided outside the substrate placed on the mounting table in a plan view, and is vertically moved outside the substrate;
further comprising another solvent collector provided to face the substrate mounted on the mounting table;
The reduced-pressure drying method includes a step of collecting a low-boiling-point solvent contained in the solution with the solvent collector, and then moving the separate solvent collector downward.

Images